The key here is to note that the young often think they can accomplish more than they actually can. For this reason, the most likely candidate, at first glance, would be "bright-eyed"; however, the option having "grandiose" for its second word is closer in that regard. The key here is to remember a (fictional) man of chivalrous idealism—Don Quixote—from whose name we derive the adjective "quixotic," meaning impractical in the pursuit of ideals. This fits just as well as "bright-eyed," if not better. Coupled with "grandiose," it makes for the correct pick.

For the first choice, "chary" works best as it means careful or cautious, while "vigilant" has a different connotation, closer to watchful for danger. The second choice must mean rash, which is the definition of "impetuous."

The writer states that his opponent is making promises that seem to be one way, but in fact are the opposite. The opposite is phrased as "no better than outright lies," so the second blank is a work that probably means false or wrong in some way. That implies that the first word is a positive one, so we are looking for a positive and negative pair of words, with the second one meaning false, illusionary, or incorrect. 

"Interesting" is not a bad choice for the first blank, as promises of economic growth would likely be interesting, but the second word, "aphoristic," is nonsensical here—it means pithy, like a brief slogan or statement. There is no connotation of truth or falsehood in connection with an aphorism, so we can rule that pair out.

"Fanciful" is a word meaning unrealistic. If this statement were in praise of the opponent's economic ideas, the statement would start out negative ("fanciful") and switch to something postive instead, such as "sound." But the second word is definitely negative, so this pair isn't right.

"Obsequious" is a word meaning "having a servile attitude". It's hard to see how this word could apply to economic ideas. And the second word, "grandiloquent," means simply talking in a grandiose manner, which says nothing about the truth of the statements being made. 

"Redundant," like "fanciful," is a negative word, meaning needlessly repetitive. This, again, does not fit the structure of the sentence, which is going from positive to negative. The second word, "egotistical," is also a negative, which does not fit.

In the correct answer, the first word is positive—"alluring", meaning attractive, which promises of economic growth certainly would be—and the second word, "meretricious," means misleading or false. This is a perfect fit and is the correct answer. 

For the first blank, we need an adjective that describes how the valley has not been developed or ruined. Either "pristine" (unspoiled) or "unspoiled" could work. For the second blank, we're looking for another adjective, this time one that means something like "clear." In choosing between "limpid," a word that specifically refers to liquids and means clear and "lucid," a word that refers to ideas or writing and means expressed in a clear way, "limpid" is the clear choice, so the answer is "pristine . . . limpid."

The sentence gives few clues, but it does tell us that the behavior of the teenagers upset the older women. So, the word that goes in the first blank must describe a personality trait that could potentially upset someone else; thus, we can eliminate "reticent" (rarely speaking) and "egalitarian" (fair and equal), neither of which make sense in the sentence. It is possible, though, that being "boorish" (ill-mannered and rude), "puerile" (immature), or "histrionic" (excessively dramatic) could upset someone else. Examining the remaining potential answers for the second blank describing the teenagers' behavior—"callow" (immature) "sophisticated" (complex or experienced) and "poised" (elegant)—only "callow" makes sense in the sentence, so "boorish . . . callow" is the correct answer.

The sentence explicitly notes that the two descriptions are "distinctly at odds," so the correct answer will have two words that mean opposite things. "Terse," meaning concise and to the point, and "loquacious," meaning extremely talkative, together make the best choice.

For the first blank, we're looking for a word that means growing, so we can eliminate the answer choices that start with "waning," "wilting," and "antediluvian." Considering the remaining choices, we're looking for a word for the second blank that means dry or dead. Since "arable" means able to be cultivated, we can eliminate that choice in favor of "desiccated," which means dried out. The correct answer choice is "burgeoning . . . desiccated." 

The sentence indicates that the man's look was angry. The only words that might fit that are "baleful" and "irate." "Sidereal" means having to do with the stars and is nonsensical here; "solicitous" means caring or inquiring; and "avaricious" means greedy. The second word has to describe darkness in a cave, which makes it impossible for the two people to see each other's faces. "Inchoate" means unformed or undeveloped, so it's not a word one would use to describe darkness. "Stygian" refers to a complete and unfathomable darkness like that thought to exist over the river Styx in mythology, so the answer is "baleful . . . stygian."

Since we can infer that the little girl did take cookies out of the cookie jar but insists that she didn't, we're looking for an adjective for the first blank that has something to do with lying. "Disingenuous" (not candid or sincere) and "mendacious" (not telling the truth) could each work. For the second blank, we need to pick between "contrite" (penitent and guilty) and "stolid" (showing little emotion). "Contrite" makes the most sense as an adjective describing the little girl's expression, since if she had a stolid expression, her parents might not have figured out she took cookies from the jar; so, the answer is "mendacious . . . contrite."

We can tell that the twins have very different personalities, so for the first blank, we are looking for an adjective that means distinct or different. "Discordant" and "disparate" are each possible choices. For the second blank, we need a word that means something like "eager." Choosing between "exigent" (demanding) and "voracious" (very hungry or eager to do something), we can pick "disparate . . . voracious" as the correct answer.